Move mixed content settings histograms into browser

content/public/browser/web_contents_observer.h

Index: content/public/browser/web_contents_observer.h
diff --git a/content/public/browser/web_contents_observer.h b/content/public/browser/web_contents_observer.h
index 5a55b72c971f4f6fde42b0698ba5bda60b6a9cff..b53a5f4ca7b4fbbfeb6c66da838f8713492fef99 100644
--- a/content/public/browser/web_contents_observer.h
+++ b/content/public/browser/web_contents_observer.h
@@ -450,6 +450,13 @@ class CONTENT_EXPORT WebContentsObserver : public IPC::Listener,
   // Notification that |contents| has gained focus.
   virtual void OnWebContentsFocused() {}
 
+  virtual void OnTriedDisplayingInsecureContent(RenderFrameHost* rfh,
+                                                const GURL& origin,
+                                                const GURL& url) {}
+  virtual void OnTriedRunningInsecureContent(RenderFrameHost* rfh,
+                                             const GURL& origin,
+                                             const GURL& url) {}
+
   // IPC::Listener implementation.
   bool OnMessageReceived(const IPC::Message& message) override;